Method and shoe for pressing segments of multi-segment filter

ABSTRACT

The object of the application is a method of pressing filter segments moving in a train of segments characterised in that the filter segments are pressed by means of a shoe ( 10, 10 A,  10′, 10 ″), whereas between the shoe undersurface ( 11, 11 A,  111, 111 A,  211, 211 A,  311, 411 ) and the filter segments (S), laid on a wrapper before gluing and covering the train of segments with the wrapper, compressed air is supplied by means of ducts ( 14, 15, 16 ). Furthermore, the object of the invention is a shoe ( 10, 10 A,  10′, 10 ″) for pressing segments of a continuous multi-segment rod characterised in that the undersurface ( 11, 11 A,  111, 111 A,  211, 211 A,  311, 411 ), for pressing filter segments (S) laid on a wrapper before gluing and covering the train of segments with the wrapper, is provided with a set of nozzles ( 17, 17 A,  19 ) for blowing in compressed air supplied through ducts ( 12, 13, 14 ).

The object of the invention is a method and a shoe for pressing segments of a multi-segment filter.

In the tobacco processing industry, cigarettes provided with filters are manufactured whereas the filters can be made of a single kind of material or can be composed of various materials with different physical and filtering characteristics. The filter material in a continuous form, such as acetate, is cut into rods and applied to cigarettes. In addition, filters manufactured of several concentrically arranged layers of the filter material are known. Filters having several segments of different materials are more and more frequently used in the cigarettes manufactured in present times. Machines for manufacturing multi-segment filter rods of continuous multi-segment filter rods are known in the prior art. Such machines combine the segments delivered from multiple feeding devices, whereas the segments are formed by cutting filter rods transferred for example on a drum conveyor using a cutting head provided with rotary knives. Individual segments are combined, depending on the apparatus, next to one another on a drum conveyor or one after another on a linear conveyor in order to finally form a linearly moving continuous multi-segment rod being cut into individual multi-segment rods. At the further stages of the cigarette manufacturing process the multi-segment rods are cut into individual multi-segment filters applied to individual cigarettes.

A very significant aspect of the production of filter rods of different known kinds is the quality of segment wrapping with a wrapper. The quality is determined by both the deformation of the wrapper in the region of an adhesive seam and the filling of the wrapper with the filter material. For the purpose of correct filling of the cylindrical space formed of the wrapper, the filter segments can be subject to a momentary compression.

Members for compression in the form of immovable pressing bars which heat up during the operation and lead to material damage are known in the prior art. The U.S. Pat. No. 3,716,443 disclosed an apparatus for manufacturing filter rods of a continuous filter material wherein a member for forming a continuous filter rod was used, whereas such member is cooled by means of compressed air. Due to the use of compressed air a thin layer reducing the friction between the filter material and the guiding members is formed.

A method for momentary compression of a continuous multi-segment rod by means of compressing rollers is known from the Polish patent application PL402777.

The problem to be solved by the present invention is to develop an improved apparatus and a method for compression of the filter material.

The substance of the invention is a method of pressing filter segments moving in a train of segments characterised in that the filter segments are pressed by means of a shoe, whereas between the undersurface of the shoe and the filter segments laid on a guiding wrapper, before gluing and covering a train of segments with the wrapper, compressed air is supplied by means of ducts.

Furthermore, the substance of the invention is a shoe for pressing segments of a continuous multi-segment rod characterised in that the undersurface for pressing the filter segments, laid on a guiding wrapper before gluing and covering a train of segments with the wrapper, is provided with a set of nozzles for blowing in compressed air supplied through ducts.

A shoe according to the invention is characterised in that the nozzles widen in the direction to the segments of a continuous multi-segment rod.

A shoe according to the invention is characterised in that the nozzles are situated in at least one row, linearly, in principle along the axis of the train of segments, preferably 3 to 10 nozzles in a single row.

A shoe according to the invention is characterised in that the rows of nozzles are arranged symmetrically to the axis of symmetry of the undersurface.

A shoe according to the invention is characterised in that the rows of nozzles are arranged asymmetrically to the axis of symmetry of the undersurface.

A shoe according to the invention is characterised in that its undersurface is a cylindrical surface.

A shoe according to the invention is characterised in that the radius of the cylindrical surface is 1.5 to 10 times greater than the radius of the segments, preferably 2 to 5 times greater.

A shoe according to the invention is characterised in that the undersurface is a flat surface.

A shoe according to the invention is characterised in that the undersurface has grooves (18) distributing compressed air.

A shoe according to the invention is characterised by being attached at an angle to the axis of the segments, in particular at an angle between 0.7° and 2°.

A shoe according to the invention is characterised in that the ducts are situated in relation to the vertical direction at an angle in the range between 0° and 30°, preferably in the range between 10° and 20°.

A shoe according to the invention is characterised in that the undersurface is situated asymmetrically to the axis of the segments.

An advantage of the solution according to the invention is the combination of two functions, namely of pressing the segments and simultaneous cooling of the surface remaining in contact with the segments being pressed.

The object of invention is shown in detail in a preferred embodiment in a drawing in which:

FIG. 1 diagrammatically shows a fragment of a machine for manufacturing multi-segment rods,

FIG. 2 shows a compressing shoe in a front view,

FIG. 3 shows a longitudinal section of a compressing shoe of FIG. 2,

FIG. 4 shows an enlarged fragment of section of FIG. 3,

FIG. 5 shows enlarged fragment of section of FIG. 3,

FIG. 6a, 6b, 7a, 7b show embodiments of undersurface of a compressing shoe provided with one row of nozzles,

FIG. 8a, 8b show embodiments of undersurface of a compressing shoe provided with a nozzle in the form of a duct,

FIG. 9 shows an embodiment of undersurface of a compressing shoe provided with three rows of nozzles,

FIG. 10 shows an embodiment of undersurface of a compressing shoe provided with two rows of nozzles,

FIG. 11 shows an embodiment of undersurface of a compressing shoe provided with multiple grooves and multiple pressing surfaces,

FIGS. 12 and 13 show cross-sections of a compressing shoe with a vertical duct,

FIG. 14 shows a cross-section of a compressing shoe with an inclined duct,

FIG. 15 shows a cross-section of a compressed filter rod before decompression,

FIG. 16 shows a cross-section of a filter rod after decompression,

FIG. 17 shows a cross-section of an asymmetrical compressing shoe with an inclined duct.

FIG. 1 diagrammatically shows a fragment of a machine for manufacturing multi-segment rods. Filter segments S prepared beforehand in a known way are delivered by a delivery unit 101 onto a conveyor 102, whereas onto its surface a wrapper 103 is placed. During the transfer of segments on the conveyor 102 the wrapper 103 is wrapped in a known way around the segments and glued, whereas the adhesive is delivered from an adhesive applying apparatus 104 and an adhesive seam is heated up by a heater 105. A multi-segment continuous rod CR formed in such a way moves further and is cut into filter rods FR by means of a known cutting head 106 provided with knives 107. Typical members supporting and guiding the continuous rod CR and the filter rods FR were omitted in the drawing. Before wrapping the wrapper 103 around the segments S and before delivering the adhesive from the adhesive applying apparatus, the segments are pressed by means of an apparatus 10 according to the invention.

FIG. 2 shows a shoe 10 for pressing segments S. It is situated above a train of segments S, whereas the wrapper has not been shown, and the segments S are arranged along the axis SA. The members for fastening and for the adjustment of position of the shoe 10 in the directions X and Y as well as in the direction perpendicular to the plane of the paper, and for the adjustment of angular position in the plane of the drawing have not been shown in the drawing. The undersurface 11 of the shoe 10 is situated along the axis SA of the train of segments S, whereas it can be deflected from the axis SA by an angle α ranging between 0.7° and 2°, i.e. the pressure of the undersurface 11 on the segments S increases in the direction of movement T of the segments S and is greatest at point 12. The effect of pressing is intensified by the action of compressed air in principle at the entire length of the undersurface 11. For this purpose, the shoe 10 for pressing segments is supplied with compressed air from a source 13. The compressed air is distributed through ducts 14 and 15 (FIG. 3), and then through ducts 16 to individual nozzles 17, whereas the nozzles 17 can have an outlet with a surface equal to the cross-section of the ducts 16 or greater. The compressed air acts on the segments S with a force F for each nozzle 17. The nozzles 17 can be situated in a row so that principally linear pressing of segments in the train of segments is achieved.

FIG. 4 shows an enlarged fragment B of a longitudinal section of the shoe 10 of FIG. 3 where the nozzles 17 have a dimension d similar to the diameter of the duct 16, whereas the nozzles are spaced at distances L to one another. The ducts 17 can be deflected from the vertical direction V by an angle β in the range between 0° and 30°, preferably in the range between 10° and 20°. FIG. 5 also shows an enlarged fragment of a section of the shoe 10A in which the nozzles 17A have a dimension D in the direction of the axis SA greater than the dimension d of FIG. 4, whereas the nozzles are also spaced at distances L to one another. Preferably the dimension D is between 1.5 of the diameter and 5 of the diameter of the duct 16. The dimension D can be similar to the dimension L or the nozzles 17A can be joined with each other forming a duct used for pressing segments with compressed air. Preferably between 3 and 10 nozzles can be situated in one row. The use of multiple nozzles allows maintaining the pressure caused by the action of compressed air at a principally constant level. The surface 17B of the nozzle, which enlarges the nozzle 17A, can have a cylindrical or conical form. FIG. 6a shows a pressing undersurface 11 provided with nozzles 17 arranged in a single row along the axis of symmetry 11X, whereas the FIG. 6b also shows an undersurface 11A provided with holes 17 arranged in a row, whereas the row of the nozzles 17 is displaced from the axis of symmetry 11X of the undersurface 11A.

FIG. 7a shows a pressing surface 111 provided with nozzles 17A arranged in a single row, whereas FIG. 7b also shows holes 17A arranged in a row, whereas the row of nozzles 17A is displaced from the axis of symmetry of the surface 111A. FIG. 8a shows a pressing surface 211 on which a nozzle in the form of a duct 19 joining the outlets of the ducts 16 is embodied. In FIG. 8b , a similar duct 19A is displaced from the axis of symmetry of the surface 211A.

FIG. 9 shows another embodiment of the undersurface 311 of a pressing shoe with three rows of nozzles 17A. FIG. 10 shows an embodiment of the surface 411 with two rows of nozzles 17A, whereas the nozzles are situated asymmetrically to the axis of symmetry of the surface 411. The use of multiple rows allows a more uniform distribution of pressure on the segment surfaces.

FIG. 11 shows another embodiment of the undersurface 511 of the shoe which is divided by the grooves 18 into multiple component surfaces 511A. The compressed air is supplied to the ducts 18 through the ducts 16.

FIG. 12 shows a cross-section through a shoe 10 and a duct 16 marked as A-A in FIG. 2, whereas here a wrapper 14 is shown on which the segments S are situated. A contour of the segment S without pressing is marked with a broken line, whereas the segment S′ shows a segment after pressing by the force caused by the pressure of the shoe 10 and the action of compressed air. The undersurface 11 of the shoe can have a cylindrical form with an axis principally perpendicular to the axis AS of the train of segments S, whereas the radius R of the cylindrical surface is between 1.5 and 10 times, preferably between 2 and 5 times, greater than the radius r of the segment. Such proportions of the radius of the undersurface to the radius of the segment allow suitable lining of the deformed surface of the segment to the undersurface of the shoe. An embodiment of the undersurface of the shoe in the conical or flat form is also possible.

FIG. 14 shows a shoe 10′ provided with ducts 16 supplying compressed air at an angle γ to the vertical direction V in the range between 5° and 20° so that the compression effect is strengthened. Due to an asymmetrical situation of the nozzles 17 relative to the segment S, it is possible to make a momentary pressing P (FIG. 15) of the segment S laterally in relation to the adhesive seam G. After the decompression of material of the segment S the glued wrapper 14 will be filled as shown in FIG. 16. FIG. 17 shows a section through a shoe 10″ constructed in principle similar to the shoe 10′ of FIG. 14, whereas the surface 11″ is situated asymmetrically to the segment S. 

1. A method of pressing filter segments moving in a train of segments characterised in that the filter segments are pressed by means of a shoe (10, 10A, 10′, 10″), whereas between the undersurface of the shoe (11, 11A, 111, 111A, 211, 211A, 311, 411) and the filter segments (S) laid on a wrapper, before gluing and covering the train of segments with the wrapper, compressed air is supplied by means of ducts (14, 15, 16).
 2. A shoe (10, 10A, 10′, 10″) for pressing segments of a continuous multi-segment rod characterised in that the undersurface (11, 11A, 111, 111A, 211, 211A, 311, 411), for pressing filter segments (S) laid on a wrapper before gluing and covering the train of segments with the wrapper, is provided with a set of nozzles (17, 17A, 19) for blowing in compressed air supplied through ducts (12, 13, 14), and the nozzles (17A) widen in the direction to the segments (S) of the continuous multi-segment rod.
 3. (canceled)
 4. The Shoe as in claim 2 characterised in that the nozzles (17, 17A) are situated in at least one row, linearly, in principle along the direction of an axis (SA) of the train of segments (S), preferably 3 to 10 nozzles in a single row.
 5. The shoe as in claim 2 characterised in that the rows of nozzles are arranged symmetrically in relation to the axis of symmetry of the undersurface (11, 11A, 111, 111A, 211, 211A, 311, 411).
 6. The shoe as in claim 4 characterised in that the rows of nozzles are arranged asymmetrically in relation to the axis of symmetry of the undersurface (11, 11A, 111, 111A, 211, 211A, 311, 411).
 7. The shoe as in claim 2 characterised in that its undersurface (11, 11A, 111, 111A, 211, 211A, 311, 411) is a cylindrical surface.
 8. The shoe as in claim 7 characterised in that the radius (R) of the cylindrical surface is between 1.5 and 10 times greater than the radius (r) of the segments, preferably between 2 and 5 times greater.
 9. The shoe as in claim 2 characterised in that the undersurface is a flat surface.
 10. The shoe as in claim 2 characterised in that the undersurface has grooves (18) distributing compressed air.
 11. The shoe as in claim 2 characterised in that the shoe (10, 10A, 10′, 10″) is attached at an angle to the axis (SA) of the segments, in particular at an angle between 0.7° and 2°.
 12. The shoe as in claim 2 characterised in that the ducts (14, 15, 16) are situated relative to the vertical direction (V) at an angle (β) in the range between 0° and 30°, preferably in the range between 10° and 20°.
 13. The shoe as in claim 2 characterised in that the undersurface (10, 10A, 10′, 10″) is situated asymmetrically to the axis of the segments (S).
 14. The shoe as in claim 2 characterised in that its undersurface (11, 11A, 111, 111A, 211, 211A, 311, 411) is a cylindrical surface.
 15. The shoe as in claim 4 characterised in that its undersurface (11, 11A, 111, 111A, 211, 211A, 311, 411) is a cylindrical surface.
 16. The shoe as in claim 5 characterised in that its undersurface (11, 11A, 111, 111A, 211, 211A, 311, 411) is a cylindrical surface.
 17. The shoe as in claim 6 characterised in that its undersurface (11, 11A, 111, 111A, 211, 211A, 311, 411) is a cylindrical surface.
 18. The shoe as in claim 4 characterised in that the undersurface is a flat surface.
 19. The shoe as in claim 5 characterised in that the undersurface is a flat surface.
 20. The shoe as in claim 6 characterised in that the undersurface is a flat surface. 